1. Technical Field
The present invention relates to a lens unit where at least three lenses are laminated and received in a lens barrel, and more particularly, to a lens unit that is resistant to an impact applied from an object.
2. Related Art
In the past, there has been known a lens unit where a plurality of lenses is received in a cylindrical lens barrel so as to be laminated. The lens unit has been used not only for camera modules of a digital camera, a mobile phone with a camera, and the like, but also for an in-vehicle camera that is used to monitor the rear side of an automobile. There is, for example, a lens unit disclosed in Japanese Unexamined Patent Application Publication No. 2008-52196 as a lens unit where a plurality of lenses is laminated in a lens barrel as described above.
When a lens unit is used for an in-vehicle camera, there is a supposed case where an impact is applied to a lens by a flying stone, or the like. Accordingly, it is necessary for an in-vehicle camera not to be damaged when a certain impact is applied to a lens unit. In a lens unit in the related art, lenses merely come in contact with each other at peripheral portions. For this reason, when an impact is applied to the lenses, the impact is directly transmitted between the lenses. Therefore, there has been a problem in that the lenses are apt to become damaged.